Occurrence of enterotoxins, exfoliative toxins and toxic shock syndrome toxin-1 genes in Staphylococcus aureus and CoNS isolated from clinical and food samples in Algeria

Abstract

The aim of this study was to determine the occurrence of toxin-genes carried by strains of Staphylococcus aureus and Coagulase Negative Staphylococci (CoNS) in Algeria. The present study performed two set multiplex PCR assay using specific primers for screening of 8 genes encoding for classical enterotoxins (SEs) (sea to see), Exfoliative Toxins (eta, etb) and Toxic Shock Syndrome Toxin-1 (tst). We analyzed 51 strains isolated from food samples and 45 strains originated from clinical cases. We observed that more than half of food strains (52.94%) possessed at least one of SEs genes; where S. aureus appears to be potentially enterotoxigenic than CoNS (68.18% vs 41.37%). From all the SEs genes amplified (27), sed gene (19;70.37%) was the most frequently detected. In clinical isolates, only 6 (13%) S. aureus harboured at least one SEs genes. However, 55.55% of clinical isolates (S. aureus or CoNS) possessed tst gene for Toxic Shock Syndrome Toxin-1. There were no foods or clinical isolates detected to possess exfoliative toxins genes (eta, etb). In conclusion, this study showed high frequency of SEs genes in food isolates, and tst gene in clinical isolates; our findings provide updated data on the Staphylococci toxins carriage in Algeria.